9:00 AM - 9:15 AM
[13a-2B-1] Performance Evaluation in Refractive Index Measurement of Sucrose Solutions using SOI Photodiode with Surface Plasmon Antenna
Keywords:SOI photodiode,surface plasmon antenna,refractive index measurement
Refractive index (RI) measurement has found variety of applications in the fields of agriculture, chemistry, biology, medicine, etc. Especially, RI-based detection of a trace of biomaterial without relying on fluorescence label has been extensively researched using many types of optical sensors. However, most of them need a complicated optical system, because the light source and the photodetector must be arranged separately from the sensor surface. It has also been a challenge to integrate a large number of sensors on a chip for high-throughput analysis.
Recently, we have proposed a silicon-on-insulator (SOI) photodiode (PD) with surface plasmon (SP) antenna. The PD has unique and advantageous features for RI measurement. One is the enhanced light sensitivity with sharp peak at a specific wavelength in the spectroscopic characteristics. Based on the shift in the peak wavelength, the PD can sense the RI around SP antenna. The other is the small sizes of the PD in several tens of micrometers. Accordingly, it becomes possible to integrate a large number of sensors in a single chip.
In this report, the refractive index (RI) measurements of sucrose solutions using SOI PD with SP antenna will be demonstrated. The sensitivity and the detection limit in RI measurement are obtained from the sensorgram of the measured photocurrents when the sucrose solutions with various concentrations are introduced around the SP antenna. In contrast to other RI-based biosensors, the optical system of our sensor is much simpler, the sizes are small, and it can be integrated with CMOS circuits. The results may open up new horizons for high-throughput fluorescence-label-free biosensing.
Recently, we have proposed a silicon-on-insulator (SOI) photodiode (PD) with surface plasmon (SP) antenna. The PD has unique and advantageous features for RI measurement. One is the enhanced light sensitivity with sharp peak at a specific wavelength in the spectroscopic characteristics. Based on the shift in the peak wavelength, the PD can sense the RI around SP antenna. The other is the small sizes of the PD in several tens of micrometers. Accordingly, it becomes possible to integrate a large number of sensors in a single chip.
In this report, the refractive index (RI) measurements of sucrose solutions using SOI PD with SP antenna will be demonstrated. The sensitivity and the detection limit in RI measurement are obtained from the sensorgram of the measured photocurrents when the sucrose solutions with various concentrations are introduced around the SP antenna. In contrast to other RI-based biosensors, the optical system of our sensor is much simpler, the sizes are small, and it can be integrated with CMOS circuits. The results may open up new horizons for high-throughput fluorescence-label-free biosensing.